Multi-headed tamper staggered operation

ABSTRACT

The invention relates to method and apparatus for tamping railway track ballast with a tamping machine having a fixed tamping head and a second tamping head movable along the machine chassis, the tamping heads being operated in a sequence such that whilst the first tamping head is conducting its tamping cycle the second tamping head is moving on the chassis and whilst the second tamping head is conducting its tamping cycle, the fixed tamping head is moving along the track, the tamping cycles of the heads overlapping each other with a substantially 180* phase difference.

United States Patent 1191 1111 3,808,976

Stewart May 7, 1974 [54] MULTl-HEADED TAMPER STAGGERED 3,680,486 8/1972 Plasser et al 104 12 OPERATION R27,604 3 1973 Stewart et al 104/12 [75] Inventor: gogn Kenneth Stewart, Columbia, Primary Examiner Robert G Sheridan Assistant Examiner-Richard A. Bertsch [73] Assignee: Canron, Inc., Phillipsburg, NJ.

221 Filed: Sept. 27, 1972 [57] ABSTRACT The invention relates to method and apparatus for PP N05 292,716 tamping railway track ballast with a tamping machine having a fixed tamping head and a second tamping [52] US. Cl. 104/12, 104/8 head movable along the machine chassis the tamping 51 1m. (:1 EOlb 33/02, EOlb 27/17 heads being Operated in a Sequence Such that whilst 58 Field of Search 104/12, s, 7 B; 404/72 the first tamping head is conducting its tamping cycle the second tamping head is moving on the chassis and 5 References Cited whilst the second tamping head is conducting its tamp- UNITED STATES PATENTS ing cycle, the fixed tamping head is moving along the track, the tamping cycles of the heads overlapping 3,687,081 8/1972 Plasser et al 104/12 o 2,734,463 2,1956 Hursh et a1 104,12 each other with a substannally l80 phase difference. 3,380,395 4/1968 Plasser et al 104/ 12 6 Claims, 3 Drawing Figures UPFEED U CONTROL CARRIAGE TRAVEL CONTROL UPFEED CONTROL SOUEEZE 36 PRESS SWITCH SOUEEZE PRESS SWITCH HYDRAULIC 2s CARRIAGE MOTOR OWER TIE INDEXER 23 INDEXER 27 LIMIT LI SWITCH SWITCH ELECTRICAL CONNECTION HYDRAULIC CONNECTION PATENIEIIIIII IIIII 7 3808976 SHEET 2 [1F 3 "CYCLE" CONTROL OPERATED FRONT W/H'S DOwN-FEED a SQ.-IN I FRONT W/H'S INITIAL START-UP E G 2. BEGIN SEQUENCE UPFEED REAR W/H'S BEGIN DOwNFEED I IAND OR REAR W/H'S MACHINE BEGIN TRAVELS SO.IN FORwARD REAR w/I-Is FRONT FINISH INDExER I SO.-IN FINDS TIE suBSEOuENT I l CYCLES AND LOOP REAR W/H'S REAR FRONT TRAVEL UPFEED w/HS FORWARD DOWNFEED REAR I INDExER WRQ K S FINDS TIE SO-IN I r I REAR w/I-IS FRONT w/I-I'S DOwNFEED BEGIN I UPFEED MULTI-HEADED TAMPER STAGGERED OPERATION BACKGROUND OF THE INVENTION The present invention relates to a method and means of tamping railway track ballast with a multiple head tamping machine on which at least one of the tamping heads are movable on the machine chassis relative thereto and particularly, but not exclusively, to a method and means for tamping railroad track ballast with a machine having a fixed tamping head and a second tamping head movable on the machine chassis and relative thereto.

Machines have been suggested heretofore in which a plurality of heads were mounted on a chassis of a tamping machine, the heads being movable along the chassis and proposals have been made for permitting a movable tamping head to remain in the ballast to complete its tamping cycle whilst the machine moved forwardly along the track, the tamping head, on completion ofits tamping cycle, being raised and rushed forward along the chassis to an appropriate stop so as to be positioned correctly for the next simultaneous down-feeding of all the tamping heads into the ballast. Such a proposal allowed for a slow, virtually continuous, forward motion of the machine chassis.

It has also been proposed (see copending U.S. Pat. application Ser. No. 79,773 filed Oct. 12, 1970) now US. Pat. No. 3,714,901, issued Feb. 6, 1973 to stagger the operation of two tamping heads such that the peak power requirement of each tamping head will not coincide.

There has been a further proposal to sequence the operation a second tamping head mounted for movement on a machine chassis in relation to a fixed front head mounted on the machine, so that if the front tamping head encounters the tie which it is to tamp before the rear movable tamping head encounters the tie which it is to tamp, the machine will stop with the fixed tamping head above the tie which it is to tamp whilst the second tamping head is moved along the chassis forwardly until it encounters the tie which it is to tamp. Alternatively if the rear tamping head encounters its tie before the front tamping head is correctly positioned, the rear tamping head is moved rearwardly on the chassis at the same speed as the forward motion of the machine chassis so that the movable tamping head keeps station above the tie which it is to tamp until such time as the fixed head is positioned over its tie.

The prior proposals suffered from the disadvantages that in every case, the speed of operation of the machine would have to be slowed to wait the positioning of the heads, or the completion of the operation thereof. This would have been particularly true in track which had less than exact tie spacing, the usual condition found in North America and elsewhere.

SUMMARY OF THE INVENTION According to the present invention a method of railroad ballast tamping with a machine having a wheel mounted chassis carrying a first tamping head and a second tamping head mounted for movment relative thereto is improved by operating the heads in a sequence such that whilst the first head is conducting its tamping cycle the second head is moving on the chassis and whilst the second tamping head is conducting its tamping cycle, the first head is moving along the track; said tamping cycles overlapping each other with a substantially phase difference.

Under these circumstances there is no stopping of the machine to wait for a head to be positioned, or substantial delay of the machine to permit a head to complete its tamping cycle. The result is that a machine having two tamping heads can tamp track at the speed of operation of two single headed machines, each tamping every second tie. It will be obvious that this is especially an advantage in tamping track which has an irregular tie spacing.

The present invention also provides a railroad ballast tamping machine comprising a wheel-mounted chassis; first and second tamping heads thereon; means for down-feeding and up-feeding the tamping heads into and out of the ballast; means for squeezing-in the tamping heads in the ballast to consolidate the ballast beneath ties being tamped; means for propelling the first head along the track; means for moving the second tamping head on the chassis relative thereto; control means operatively interconnecting the first tamping head with the second tamping head and operable to down-feed the second tamping head on substantial completion of the squeezing-in of the first tamping head and to down-feed the first tamping head on substantial completion of the squeezing-in of second tamp ing head; means responsive to the up-feeding of the first tamping head to operate the means to propel the first head along the track; and means responsive to the up-feeding of the second tamping head to operate the means for moving the second tamping head relative to said chassis: whereby the first tamping head is pro pelled along the track whilst the second tamping head is conducting its tamping cycle and the second tamping head is moved on the chassis whilst the first tamping head is conducting its tamping cycle; said tamping cycles being substantially 180 out of phase with one another.

In a preferred embodiment the first tamping head is fixed on the chassis and the means to propel it along the track is the machine prime mover.

BRIEF DESCRIPTION OF THE DRAWINGS The following is a description by way of example of one embodiment according to the present invention reference being bad to the accompanying drawings in which: 1

FIG. 1 is a diagrammatic representation of a machine having a fixed front head and a movable rear head;

FIG. 2 is a block flow-diagram showing the sequence of operations according to the method of the invention; and

FIG. 3 is a diagrammatic representation of the timing of the sequence of operations in accordance with the method of the invention.

DESCRIPTION OF SPECIFIC EMBODIMENT raising the frame 18 and the tamping tools 17 thereon out of the ballast (they are dropped into the ballast under their own weight) and squeeze cylinders 20 of standard configuration are provided to squeeze the tamping tools 17 together beneath a tie to be tamped in the fashion well known and shown in the dotted lines in the figure. Mounted intermediately of the wheels 12 of the machine is a second tamping head 22, of a virtually identical configuration to the head 20. The rear head 22 is mounted for longitudinal movement on the chassis on a rack 23 and is propelled therealong by means of a pinion gear 24 driven by a hydraulic carriage motor shown diagrammatically at 25. Although only the tampinghead over the rail visible in the drawings is shown, it is to be understood, that in standard fashion, the illustrated heads have companion heads in line with them over the other rail of the track. The forward motion of the vehicle under the action of the hydraulic traction motor 13 is terminated by means of a tie indexer 27 in standard fashion and forward movement of the head 22 and its frame on the rack 23 is terminated by a second standard tie indexer 28 mounted on the moving tamping head 22 and controlling the hydraulic carriage motor 25 in known manner.

At the front of the machine there is provided a standard track lifting jack diagrammatically shown at 30 and an aligning jack diagrammatically shown at 31.

Limit switches 32 and 33 are provided on the chassis l1 and are tripped by movements of the heads and 22 past them. Also the squeeze cylinders and 20R for the rear head are connected in conventional fashion to squeeze pressure switches 35 and 36.

The operational method according to the invention will not be explained with reference to FIGS. 1, 2 and Let it be assumed that the machine has just been started and is positioned such that both the front and rear tamping heads are located over the ties which they are to tamp. A cycle control" switch C has been operated and the tie indexer 27 has encountered its reference tie and sent a signal to the machine travel control T to stop the hydraulic traction motor 13. At the same time a signal is fed from the indexer 27 to the downfeed control D to drop the front heads 15 into the ballast. As the head 15 falls it trips a switch 32 which transmitts a signal to initiate the squeeze-in of the cylinders 20 in standard fashion. As the squeeze cylinders 20 reach a predetermined pressure the squeeze pressure switch 35 is operated and a signal is sent to the upfeed control U which operates cylinder 19 to prepare to lift the front head 15 out of the ballast while its squeeze cylinders 20 operate to squeeze out the tools 17, away from each other. As the head 15 up-feeds out of the ballast it again trips the switch 32 which sends a signal to the machine travel control T to actuate the hydraulic traction motors 13 to move the machine and an additional signal is sent to the down-feed control D of the rear work head. This causes the rear work head to drop into the ballast and to commence the squeezing of the heads by means of the squeeze cylinders 20R. The rear head 22 works in the ballast to tamp its tie as the machine moves forward relatively to it. The hydraulic carriage motor being deactivated and the weight of the rear heads 22 in the ballast permitting the rack 23 to move with the chassis 11 relative to the pinion 24.

On completion of the squeeze-in of the rear head 22 the squeeze pressure switch 36 is operated and a signal is sent to the up-feed control U for the rear head to prepare to lift the rear head 22 out of the ballast and squeeze-out the squeeze cylinders 20R. Thus as soon as the front indexer reaches its tie, a signal is transmitted to up-feed the rear head 22, stop the machine and down-feed the front head 15. As the rear head 22 passes lower limit switch 33 it trips it and a signal is transmitted to the carriage travel control T, in conventional fashion, to operate the hydraulic carriage motor 25 to move the head 22 forwardly on the chassis 11 by driving the pinion 24 along the rack 23. This continues until the tie indexer 28 encounters the tie which it is to tamp whereupon a signal is transmitted to terminate the action of the motor 25 and trigger the down-feed of the rear head 22 and'the up-feed of head 15.

It will thus be observed that the tamping heads are operating substantially out of phase with each other.

Preferably the track lifting and track lining operation by means of the jacks 30 and lining cylinders 31 are controlled by the front tie indexer in known fashion through the lift and line controls L so that when the ma chine is stopped over the tie which the front head is to tamp, the track is lifted and lined during the sequence of the tamping operation of the front tamping head.

Although the invention has been described with reference to a machine having a fixed head and a movable head, it is to be understood that the invention is equally applicable to machines having no fixed head but a plurality of moving heads carried on a constantly moving frame.

What I claim as my invention is:

1. In a method of railroad ballast tamping with a machine having a wheel mounted chassis carrying a first tamping head and a second tamping head mounted behind said first tamping head for movement relative thereto, the improvement comprising operating said heads ina sequence such that whilst the first head is conducting its tamping cycle the second head is moving on the chassis towards the first head and whilst the second tamping head is conducting its tamping cycle, the first head is moving along the track away from the second head; said tamping cycles overlapping each other with a substantially 180 phase difference.

2. In a method of railroad ballast tamping with a machine having a wheel mounted chassis carrying a fixed tamping head and a tamping head mounted for movement relative thereto, the tamping cycles of each head comprising the steps of down-feeding into the ballast, squeezing-in to consolidate ballast beneath a tie being tamped, and squeezing-out and up-feeding from the ballast after consolidation; the improvement comprising operating said heads in sequence such that whilst the front head is conducting its tamping cycle, the movable head is moving on the chassis, and whilst the movable tamping head is conducting its tamping cycle, the chassis is moving along the track; the movable head down-feed step commencing substantially at the termination of the squeeze-in step of the fixed tamping head, and the down-feed step of the fixed tamping head commencing substantially at the termination of the squeeze-in step of the movable tamping head.

3. A railroad ballast tamping machine comprising a wheel mounted chassis; first and second tamping heads thereon; means for down-feeding and up-feeding the tamping heads into and out of the ballast; means for squeezing in the tamping heads in the ballast to consolidate the ballast beneath ties being tamped; means for propelling the first head along the track; means for moving the second tamping head on the chassis relative thereto; control means operatively interconnecting the first tamping head with the second tamping head and operable to down-feed the second tamping head on substantial completion of the squeezing-in of the first tamping head and to down-feed the first tamping head on substantial completion of the squeezing-in of second tamping head; means responsive to the up-feeding of the first tamping head to operate the means to propel the first head along the track; and means responsive to the up-feeding of the second tamping head to operate the means for moving the second tamping head relative to said chassis; whereby the first tamping head is propelled along the track whilst the second tamping head is conducting its tamping cycle and the second tamping head is moved on the chassis whilst the first tamping I head is conducting its tamping cycle; said tamping cycles being substantially out of phase with one another.

4. Apparatus as claimed in claim 3 in which the first head is fixed on the chassis and the means to propel it along the track is the machine prime mover.

5. Apparatus as claimed in claim 4 in which the chassis is stopped with the first head over the tie which it is to tamp be means of a first tie indexer operatively connected to the prime mover; and the second head is located on the chassis above the tie which it is to tamp be means of a tie indexer operatively connected with the means for moving the second tamping head.

6. Apparatus as claimed in claim 5 further comprising means to lift and means to laterally shift the track; and control means operatively connecting the means to lift and the means to' laterally shift the track to said first tie indexer and operable to lift and shift the track when said tamping head is operatively positioned. 

1. In a method of railroad ballast tamping with a machine having a wheel mounted chassis carrying a first tamping head and a second tamping head mounted behind said first tamping head for movement relative thereto, the improvement comprising operating said heads in a sequence such that whilst the first head is conducting its tamping cycle the second head is moving on the chassis towards the first head and whilst the second tamping head is conducting its tamping cycle, the first head is moving along the track away from the second head; said tamping cycles overlapping each other with a substantially 180* phase difference.
 2. In a method of railroad ballast tamping with a machine having a wheel mounted chassis carrying a fixed tamping head and a tamping head mounted for movement relative thereto, the tamping cycles of each head comprising the steps of down-feeding into the ballast, squeezing-in to consolidate ballast beneath a tie being tamped, and squeezing-out and up-feeding from the ballast after consolidation; the improvement comprising operating said heads in sequence such that whilst the front head is conducting its tamping cycle, the movable head is moving on the chassis, and whilst the movable tamping head is conducting its tamping cycle, the chassis is moving along the track; the movable head down-feed step commencing substantially at the termination of the squeeze-in step of the fixed tamping head, and the down-feed step of the fixed tamping head commencing substantially at the termination of the squeeze-in step of the movable tamping head.
 3. A railroad ballast tamping machine comprising a wheel mounted chassis; first and second tamping heads thereon; means for down-feeding and up-feeding the tamping heads into and out of the ballast; means for squeezing in the tamping heads in the ballast to consolidate the ballast beneath ties being tamped; means for propelling the first head along the track; means for moving the second tamping head on the chassis relative thereto; control means operatively interconnecting the first tamping head with the second tamping head and operable to down-feed the second tamping head on substantial completion of the squeezing-in of the first tamping head and to down-feed the first tamping head on substantial completion of the squeezing-in of second tamping head; means responsive to the up-feeding of the first tamping head to operate the means to propel the first head along the track; and means responsive to the up-feeding of the second tamping head to operate the means for moving the second tamping head relative to said chassis; whereby the first tamping head is propelled along the track whilst the second tamping head is conducting its tamping cycle and the second tamping head is moved on the chassis whilst the first tamping head is conducting its tamping cycle; said tamping cycles being substantially 180* out of phase with one another.
 4. Apparatus as claimed in claim 3 in which the first head is fixed on the chassis and the means to propel it along the track is the machine prime mover.
 5. Apparatus as claimed in claim 4 in which the chassis is stopped with the first head over the tie which it is to tamp be means of a first tie indexer operatively connected to the prime mover; and the second head is located on the chassis above the tie which it is to tamp be means of a tie indexer operatively connected with the means for moving the second tamping head.
 6. Apparatus as claimed in claim 5 further comprising means to lift and means to laterally shift the track; and control means operatively connecting the means to lift and the means to laterally shift the track to said first tie indexer and operable to lift and shift the track when said tamping head is operatively positioned. 